Concentrator



Aug. R2, 1924. L5(M,Z80

A. H. STEBBINS CONCENTRATOR Fild April 12, 1922 ,2 Sheets-Sheet 1 nvVENTOI? ATTORNEY LSMWMP Aug, n2 19241.

A. H. STEBBINS 'CONCENTRATOR Filed April 12, 1922 2 Sheets-Sheet, 2

Patented Aug. 12, 1924.

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ALBERT H. STEBBINS, OF LOS ANGELES, GALIFORNIA.

CONCENTRATOR.

Application filed April 12, 1922. Serial No. 551,933.

To all whom it may concern:

Be it known that I, ALBERT H. STEBBINS, a citizen of the United States,residing at Los Angeles, in the county of Los Angeles and State ofCalifornia, have invented an Improvement in Concentrators, of which thefollowing description, in connection with the accompanying drawings, isa specification, like characters on the drawings representing likeparts.

This invention relates to concentrators of the type in which thematerials to be treated are caused to whirl about the interior of acontainer.

Concentrators are adapted to separate materials by reason of theirdifference in specific gravity,shape or frictional properties, or by acombination of two or more of these properties, and are extensively usedin the treatment of ores to separate the values from the usualimpurities.

Most ores have their values distributed throughout a relatively largeamount of impurities 01' foreign matter, and as a result the valuesobtained usually constitute a small portion of the mass of materialstreated. It is therefore important to reduce as far as practical thelabor involved in treating this mass of materials, and at the same timeto remove the values as completely as possible.

In ore treating mills it is usually desirable to concentrate thematerials at various stages of the ore treatment, and the materialscommonly are subjected'to the first concentration operation while theparticles are relatively large in size so that some of the values orconcentrates may be removed at this stage, and other values orconcentrates are removed at succeeding stages as the materials arereduced in size. In most cases the values have a higher specific gravitythan the accompanying impurities and advantage is taken of thisdifference in specific gravity in performing the concentratingoperations.

The present invention is designed more particularly for the treatment ofores or other materials that have been reduced to a line size, and oneimportant feature of the present invention consists in a containerhaving one or more tubes disposed therein in spaced relation to thewalls of the container and about which air bearing the materials to betreated is caused to whirl so that the heavier materials will be thrownoutwardly by centrifugal force.

Another important feature of the present invention consists in means fordirecting air bearing the materials to be treated upwardly into acontainer with a whirling move ment so that particles of differentspecific gravity will be carried upwardly to different heights, and inmeans for tolling off at different points along the container theparticles carried upwardly by the air.

Still another feature of the invention consists in a container having aplurality of concentric tubes therein arranged one within the other sothat air introduced into the container and bearing the materials to betreated will pass inwardly from one tube to the other and will give uppart of the materials in each tube.

Other features of the invention and novel combination of parts inaddition to the above will be hereinafter described in connection withthe accompanying drawings which illustrate one good practical formthereof.

In the drawings:

Fig. 1 is a vertical sectional view through a concentrator constructedin accordance with the present inventoin.

Fig. 2 is a'sect-ional view taken on line 2-2 of Fig. 1.

Fig. 3 is a sectional view taken on line- 3-3 of Fig. 1. 4

Fig. a is a perspective view of the lower portion of the concentrator ofFig. 1.

Fig. 5 is a side view of the lower portion of the concentrator of Fig. 1and showing the air deliveringconduit in section.

Fig. 6 is a vertical sectional view through a modified type ofconcentrator.

Fig. 7 is an enlarged sectional view on the line 77 of Fig. 6, and:

Fig. 8 is an enlarged sectional view on the line 88 of Fig. 6.

In' the present invention, concentration of the materials is effected bydirecting air carrying the materials to be treated into a container towhirl thereabout so that the heavier particles are thrown outwardly bycentrifugal force while the air and lighter particles escape from thecontainer by passing inwardly through one or more tubes arrangedcentrally within the container. In the embodiment of the invention shownin Figs. 1' to 5 inclusive a container 10 is provided having three tubes11, 12 and 13 therein arranged one inside the other to form annularchambers therebetween. The number of tubes provided, however, may beincreased or decreased as desired, and each tube pref all erably has anopeningin its wall to admit air "from the annular chamber that surroundsit.

In the embodiment of the invention illustrated air is introduced intothe lower portion of the container 10 through a conduit 14 disposedsubstantially tangentially to a wall of the container as shown in Figs.2

and 5, and having an elongated construction in cross section as shown inFig. 5 to direct the air into the container so that it will whirltherein. The lower wall of the conduit 14 preferably curves upwardly asat 15, and curves about the tube 11 in the form of a spiral 16 to directthe air upwardly with a spirally whirling movement. This spirally curvedwall 16 may serve to close the lower end of the container 10 and mayterminate at a point 17 preferably above the upper wall 18 or" theconduit 14. Various means may be provided tor causing air to enter thecontainer 10 through the conduit 14, and in the instance shown air isforced in by a fan 19. The materials to be treated may be introducedinto the path of the air either before or after it enters the container10, and in the construction shown a hopper 20 is provided upon theconduit 14 for delivering the materials into the conduit.

As stated, it is desirable to conduct the air that enters the chamber 10inwardly to pass successively through the tubes 11, 12 and 13, and tothis end, each tube is provided with aslot 21 that extends throughout asubstantial portion or the length of the tube, and adjacent each slot isprovided a lip 22 that serves to direct the air whirling adjacent a tubeinwardly through its slot. The upwardly whirling air carries thematerials upwardly into the container 10 and causes the heavierparticles to be thrown outwardly by centrifugal force against the wallsof the container, whereupon it will slide down these walls. The air fromwhich the heavier particles have been removed will enter the tube 11through the slot 21 and while whirling therein will release ad ditionalparticles and then pass into the next inner tube. Some materials will bereleased by the air in each tube and will slide downwardly therein. Theair that reaches the innermost tube 13 may be conducted from either endthereof, and in the present construction may escape from the upper endof the tube 13.

It is desirable to provide means for re moving fr m the lower ends ofthe tubes 11, 12 and 13 the materials collected therein, and to this endthe tubes are provided with discharge spouts 23, 24 and 25 respectively,each ofwhich leads into a receptacle 26 constructed to prevent air fromescaping therefrom;

In many cases it may be desirable to separate the materials that arereleased by the air in the container 10 into two or more grades, itbeing understood that materials or diiierent specific gravity will becarried upwardly to difierent heights within the container. This may bereadily accomplished by supporting the container and tubes therein at anangle inclined somewhat to the vertical as shown in Fig. 1, so that thematerials sliding downwardly within the container will travel along thelower inclined wall 27. The materials may then be tolled oif from thecontainer at different heights lengthwise thereof, and the materialsremoved at diil'erent heights will possess different specific gravity.In the construction shown the lower wall 27 of the container hasopenings 28 formed therein at spaced intervals through which the heaviermaterials sliding downwardly along the wall 27 may escape. Each opening28 may dis charge into a hopper 29 secured one above the other to thecontainer 10, and these hoppers preferably discharge into the closedreceptacles 30. A baflle plate 31 may extend across each opening 28 tocheck the whirling movement of the air that enters these openings. Itwill be understood that the upper end of the container 10 and tubes 11and 12 are closed as shown.

In some cases it may not be desirable to support the concentrator at aninclination as shown in Fig. 1, or to remove the materials therefrom atdifferent points along its length, and in this case the concentrator maybe supported in a vertical position as shown in Fig. 6. The constructionof this 'lignre differs from the construction of Figs. 1 to 5 inclusiveinthat the materials that are released by the air in the outer container32 are delivered from the container at its lower end. In thisconstruction slotted tubes 33 and 34s are disposed within the container32 as in Fig. 1 and air is led into the container through a. conduit 35disposed as in Fig. 1. In Fig. 6, however, the air from the conduit 35is directed upwardly by a plurality of radially disposed blades 36extending in an upright positionbetween the container 32 and tube 33,and the upper ends of these blades terminate one slightly above theother in the path of a spiral as shown, to deflect the incoming airupwardly. As a result of this construction the materials released by theair in the container 32 may fall downwardly into the lower end of thecontainer between the blades 36 and may be d'scharged through the spout37.

It is desirable that the area of the annular spaces between thecontainer and tubes shall be substantially the same, and this may be"provided for by successively increasing the length of the inner tubes asshown in Fig. 1 but more pronounced in Fig. 6. From the presentconstruction it will be apparent that while it is necessary to reducethe diameter of the tubes as they are placed one inside of the other, acorresponding reduction in area may be avoided by increasing the lengthof the tubes.

It will be apparent that the air moves upwardly as it passes inwardlyfrom one tube to the other, it is therefore desirable to progressivelyincrease the length of the inner tubes at their upper ends, and toincrease the length of the slots upwardly in a corresponding manner toaccommodate the upward movement of the air. The air that enters theinner tube 34imay be discharged from the upper end thereof, or from apoint near its lower end and While in most cases it may be desirable toprovide means for blowing air in through the conduit 35, it may bedesirable in some cases to draw air in through the conduit by connectingthe inner tube M with suitable exhaust means.

The feed hopper 20 should be so constructed that it will prevent the airwithin the conduit 14 from escaping through the hopper, and this may beaccomplished by providing the hopper with a restricted throat. as shown,which will normally be closed by the materials. If the materialscontinueto flow into the conduit 14: when the fan 19 is not operatingthese materials may completely close the air passage within the conduit.To prevent this apertured plates 38 may be provided within the conduit14: one above the other upon which the materials are delivered by thehopper 20, and the materials pass downwardly thru the apertures 39 fromone plate to the other. The relatively small piles of materials thatform below the apertures 39 will not ofier sufficient resistance to thepassage of air thru the conduit to completely block the passage of air,and as air squeezes thru the space between the top of a pile and theadjacent plate 38 it will increase the size of the opening by carryingoff the material.

hat is claimed is:

1. A concentrator comprising, in combination, an upwardly extendingcontainer, a plurality of tubes arranged concentrically within thecontainer and having openings in their walls for the passage of airinwardly from one tube to the other, the tubes having their length.increased in the order in which they are arranged one within the otherto increase the area of the tubes, means for introducing air bearing thematerials to be treated into the container with a spirally whirlingupward movement to throw the heavier particles outwardly by centrifugalforce, means for discharging air from the innermost tube, and means fordischarging from the container and tubes the materials deposited thereinby the air passing through the concentrator.

2. A concentrator comprising, in combination, a tubular containerextending upwardly in an inclined direction, a plurality of tubesmounted concentrically within the container to provide annular airchambers and each tube having a slot extending throughout a substantialportion of its length for the passage of air inwardly from one tube tothe other, and a conduit for delivering air loaded with the materials tobe treated tangentially into the lower portion of the container andhaving a floor portion that curves around the outer tube and is bentupwardly to direct the air upwardly with a spiral whirling movementwithin the container to throw the heavier particles outwardly bycentrifugal force away from the tube slot while the air freed from theheavier particles passes inwardly from one tube to the other through theslots.

3. A concentrator comprising, in combination, an upwardly extendingtubular container, a plurality of tubes mounted concentrically withinthe container to provide annular air chambers and each tube having aslot extending throughout a substantial portion of its length for thepassage of air inwardly from one tube to the other, and a conduit fordelivering air loaded with the materials to be treated into the lowerportion of the container with an upward whirling movement, and a floorportion that curves upwardly around the outer tube to direct the airupwardly with a spiral whirling movement about the container to throwthe heavier particles outwardly away from said slot while the air freedfrom the heavier particles passes inwardly from one tube to the otherthrough the slots,

. 4:, A concentrator comprising, in combination, an upwardly extendingtubular container, a plurality of tubes mounted concentrically withinthe container to provide annular air chambers and each tube having aslot extending throughout a substantial portion of its length for thepassage of "air inwardly from one tube to the other, means fordelivering air loaded with the materials to be treated into the lowerportion of the container with an upward whirling move ment that causesthe air to whirl about the container to throw the heavier particlesoutwardly away from said slot while the air freed from the heavierparticles passes inwardly from one tube to the other through the slots,and lips at the slots for directing the air whirling adjacent a tubeinwardly through its slot.

5. A concentrator comprising, in com bination, an upwardly extendingtubular container, a plurality of tubes mounted concentrically withinthe container to provide annular air chambers and each tube having aslot extending throughout a substantial portion of its length for thepassage of air inwardly from one tube to the other, means for deliveringair loaded with the materials to be treated into the lower. portion ofthe container with an upward whirling movement that causes the air towhirl about the container to throw the heavier particles outwardly awayfrom said slot while the air freed from the heavier particles passesinof tubes mounted concentrically within the container to provideannular air chambers and each tube' having a slot extending throughout asubstantial portion of its length for the passage of air inwardly fromone tube'to the other, means for delivering air bearing the materials tobe treated into the lower portion of the'container and for directing theair upwardlywith a spiral whirling movement within the container tothrow the heavier particles outwardly by centrifugal force away from thetube slot while the air freed from the heavier particles passes inwardlyfrom one tube to the otherthrough the slots, and means: at the underside of the inclined container for telling oif at different pointslengthwise of the container the heavier particles carried upwardly bythe air.

7. A concentrator comprising, in combination, an upstanding container, atube within the container and forming an annular air passage within thecontainer and the tube having a slot extending throughout a substantialportion of its length for the passage of air inwardly from thecontainer, means for directing air bearing the mate rials to be treatedsubstantially tangentially into the lower portion of the container andfor directing it upwardly therein to cause the air to whirl about thetube as it rises within the annular chamber to cause the heavierparticles to be thrown outwardly by centrifugal force away from saidslot while the air from which the heavier materials are removed passesinwardly into the tube to whirl therein and release from the air additional particles, and means for receiving the materials that settle inthe lower portion of the container and tube.

8. A concentrator comprising, in combination, an upstanding container, atube extending through the container to form an annular chamber thereinand projecting from the lower end of the container, said tube having aslot extending throughout a substantial portion of its length for thepassage ofair inwardly from the container, a conduit for directing airbearing the material to be treated tangentially into the lower portionof the container and having a floor portion that curves around the lowerportion of the tube and is bent upwardly to direct the air upwardlywithin the annular chamber with a spiral whirling movement that throwsthe heavier particles outwardly by centrifugal force away from said.slot while the air from which the heavier materials are removed passesinwardly into the tube to whirl therein for further treatment.

In testimony whereof, I have signed my name to this specification.

ALBERT H. STEBBINS.

